Premiere Pro-can't get free trial

I have already had premiere pro's free trial and also have bought premiere pro for a month for a class I needed to edit video in. I turned in a project and saved it as a .prproj file. I just found out I was supposed to save it as a .mp4 file. Now my subscription has ended and I can't get back into the app to change the file. I don't want to have to pay for another month to change one thing that will take me a couple of minutes. What can I do?